"Units from all of the country's force structures are participating. May God be with us," the minister wrote on his Facebook page.
Yesterday Avakov hit out at what he called a "display of aggression by Russia" as heavily armed separatist militants launched a series of attacks on police headquarters across the eastern rust belt.
The highly organised offencive by men in unmarked military uniforms was reminiscent of that which took place in Crimea in March, fanning fears that Russia is stoking unrest as a pretext to intervene in the neighbouring country.
Moscow yesterday warned Kiev against using force against the militants, whose demands range from being granted greater autonomy to joining Russia.
Ukraine's security council met late yesterday for more than three hours to discuss the crisis in the east, but no decision has been announced.